Perhaps the most common toilet system for recreation vehicles (also known as caravans) is a cassette system in which a gravity toilet is mounted above a compartment. A holding tank is slidable into and out of the compartment to mate with the bottom of the toilet. The holding tank has a sliding valve which is activated by a flush activator on the toilet. When the holding tank is slid into the compartment, channels on the holding tank engage the connection flange on the toilet to properly position the holding tank, and the actuator for the slide valve automatically engages the flush actuator. Such a system is shown in U.S. Pat. Nos. 4,776,631 and 5,031,249, the disclosures of which are hereby incorporated by reference herein.
While the heretofore described system is very successful, it can be unpleasant to use particularly at relatively long stays at a campground. The system described above requires deodorant chemical be added on a regular basis, and requires almost daily emptying, which is an unpleasant task. Therefore, it is highly desirable to be able to use an alternative to the prior art system described above when there is a relatively long stay at a campground. This would be particularly desirable for use at campgrounds having vacuum systems such as described in copending application Ser. No. 08/996,876, filed Dec. 23, 1997 (the disclosure of which is hereby incorporated by reference herein).
According to the present invention, in order to convert the low water usage, gravity toilet system as described in U.S. Pat. Nos. 4,776,631 and 5,031,249 into a vacuum system, a simple change is made to the existing system. The conventional holding tank for the system is withdrawn and not used, and the vacuum adaptor is slid into the compartment vacated by the holding tank and the same connection system is used to connect the vacuum adaptor to the connection flange of the toilet. Preferably, also the same flush actuator for the toilet can be utilized, the actuator for the vacuum adaptor movable valve automatically moving into place when the vacuum adaptor is properly aligned with the toilet. The vacuum adaptor has its own self-contained substantially airtight valve since the adaptor will be connected up to a vacuum system. The movable valve element may comprise an arcuate element that is rotated about a substantially horizontal axis when the toilet flush actuator is actuated.
According to one aspect of the present invention a method of hooking up to a substantially stationary vacuum source having at least one hookup an onboard sewage system of a recreational vehicle is provided. The recreational vehicle sewage system includes a toilet, a holding tank slide connected to the toilet, a valve mounted to the holding tank between the holding tank and the toilet, and a compartment for removably receiving the holding tank, disposed under the toilet. The method comprises the steps of: (a) Parking the recreation vehicle near the stationary vacuum source at least one vacuum source hookup. (b) Removing the holding tank from the compartment, disconnecting the holding tank from the toilet. (c) Inserting a vacuum adaptor having a substantially airtight valve into the compartment in place of the holding tank to connect the vacuum adaptor to the toilet so that when the toilet is flushed the valve is opened and sewage passes from the toilet into the vacuum adaptor. And (d) connecting the vacuum adaptor to the at least one vacuum source hookup.
Preferably the recreational vehicle has a pre-existing flush actuator for the toilet, and the vacuum adaptor valve has a valve actuator; and step (c) is practiced to connect up the valve actuator of the vacuum adaptor to the pre-existing flush actuator for the toilet (this connection preferably automatically taking place when the vacuum adaptor is slide into the compartment). Step (d) is preferably practiced using a spring biased dripless connection between the vacuum adaptor and the vacuum source hookup. Step (b) is preferably practiced by sliding the holding tank out of the compartment, and step (c) is practiced by sliding the vacuum adaptor into operative association with the toilet. The toilet typically has a connection flange, and step (c) is preferably practiced by sliding a pair of channels on the vacuum adaptor into operative contact with a connection flange. The substantially airtight valve of the vacuum adaptor includes a rotatable valve element; and the method preferably comprises the further step of flushing the toilet by effecting rotation of the rotatable valve element from a closed to an open position.
According to another aspect of the present invention a vacuum adaptor for use instead of a holding tank for a pre-existing recreation vehicle toilet, having a connection flange, is provided. The adaptor comprises: The substantially hollow body having a top, bottom, and at least one side. A connection at the body top for connecting the body to the connection flange of a recreation vehicle toilet. A substantially airtight valve in the body, and having a movable valve element disposed in operative association with the connection. An actuator for the movable valve element, disposed in part exteriorly of the body. And a vacuum source connector extending from the at least one side or bottom of the body, and configured for connection to a vacuum source.
The vacuum source connector preferably comprises a dripless connector. Preferably the actuator includes: A first actuator element rotatable about a substantially vertical axis and connectable up to a pre-existing recreation vehicle toilet flush actuator; a second actuator element rotatable about a substantially horizontal axis for rotating the movable valve element about the same substantially horizontal axis; and a valve actuator connector connecting the first and second actuator elements to translate rotation of the first actuator element into rotation of the second actuator element.
Typically the movable valve element comprises an arcuately shaped element making a seal with a sealing material (e.g. an elastomeric material) as the movable valve element moves between opened and closed positions. The movable valve element is preferably mounted for rotation about a substantially horizontal axis.
Typically the connection at the body top comprises a pair of spaced slide channel-defining elements including upper portions and lower portions. The lower portions engage the movable valve element and make sealing contact therewith. The lower portions may be elastomeric material strips. The movable valve element is preferably spring biased to a closed position.
The apparatus according to the invention preferably further comprises a vacuum source hookup disposed at a campground, and comprising one of a plurality of vacuum source hookups at the campground. The vacuum source hookup is connected to a vacuum tank at the campground, or such other structure such as disclosed in said copending application Ser. No. 08/996,876. Preferably the vacuum tank is mounted substantially below ground, and is connected to a vacuum pump.
It is a primary object of the present invention to provide a simple yet effective method and apparatus for converting a conventional recreation vehicle non-vacuum toilet system to a vacuum system at a campground or the like, so as to eliminate the necessity of manually emptying the holding tank, or adding significant amounts of deodorant chemical, while at the campground or the like. This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.